FAQ

How to Use Updatable ResultSet in JDBC?

A default ResultSet object is not updatable and has a cursor that moves forward only. Thus, you can iterate through it only once and only from the first row to the last row. It is possible to produce ResultSet objects that are scrollable and/or updatable. An updatable result set allows modification to data in a table through the result set. The following code makes a result set that is scrollable and insensitive to updates by others:

to update a column value in the current row. In a scrollable ResultSet object, the cursor can be moved backwards and forwards, to an absolute position, or to a position relative to the current row. The following code fragment updates the Office column in the fifth row of the ResultSet object rs and then uses the method updateRow to update the data source table from which rs was derived.

rs.absolute(5); // moves the cursor to the fifth row of rs rs.updateString("Office", "HQ222"); // updates the // Office column of row 5 to be HQ222 rs.updateRow(); // updates the row in the data source

to insert column values into the insert row. An updatable ResultSet object has a special row associated with it that serves as a staging area for building a row to be inserted. The following code fragment moves the cursor to the insert row, builds a three-column row, and inserts it into rs and into the data source table using the method insertRow.

to delete a row. The following code fragment moves to the first row of the ResultSet object rs and then uses the method deleteRow to delete the data source table from which rs was derived.

rs.first(); // moves cursor to the deleting row rs.deleteRow();

A ResultSet object is automatically closed when the Statement object that generated it is closed, re-executed, or used to retrieve the next result from a sequence of multiple results.

cancelRowUpdates cancels the updates made to the current row in this ResultSet object. This method may be called after calling an updater method(s) and before calling the method updateRow to roll back the updates made to a row. If no updates have been made or updateRow has already been called, this method has no effect.